Temperature, wind, salinity and current

This page shows a catalogue of videos generated from the eReefs Hydrodynamic model. Click on a month to choose the period of the video or click on the map to zoom in on a region.

This combination shows key hydrodynamic parameters of the Great Barrier Reef. These map layers are also available for inspection as an interactive map. You can also access the raw data from NCI THREDDS server (hourly) and the aggregate data from the AIMS eAtlas THREDDS server (daily, monthly, yearly, all).

Clear bifurcation of the currents around Lizard island, north of Cairns (Oct 2014)

Temperature

The temperature is primarily driven by the seasons and mixing of the water by wind and ocean currents. If the temperature rises too high during summer months then it can cause corals to bleach. This can be see during the summer months of 2016 and 2017.

Wind

The wind is a key driver of surface water currents, mixing and waves. In summer months when the wind is low the surface temperatures rise significantly during the day, resulting in a "heart-beat" in the temperature in the video. The wind also drives the direction of the flood plumes, typically blowing north west making them hug the coast. When the wind occasionally blows offshore then the plumes are pushed further out.

The path of cyclones can be seen in the wind variable. This shows the asymmetrical shape of the cyclone as it approaches the coast, due to the friction of the land slowing the winds on the southern side of the cyclone.

Note: The winds in this model come from the BOM ACCESS meteorological product. This wind model does not accurately capture peak intensity of the cyclone or its exact path. It tends to underestimate the peak wind speeds.

Salinity

Low salinity (dark blue) occurs due to river out flows causing flood plumes and rain events. This is a good proxy for where plume waters might be. During flood plumes if the wind is blowing offshore then it will push the plume off the coast more toward the reefs. 2011 was a particularly wet year during the summer months causing extensive plumes to drift of reefal areas.

Current

The currents are drived by the wind, tides, and temperature and salinity gradients as these change the density of the water. In the visualisations the strength of the current is represented by colour and the arrows represent the direction. In the hourly data it is possible to see the tidal currents causing the direction of the current to flip back and forth. This tidal current increases the mixing of the water causing sediment in inshore areas to be stirred up. In the daily and monthly visualisations most of the fluctuations of the tidals have been averaged out, allowing some of the large scale current flow patterns to be seen.